Making sense of our world is often linked to our ability to predict what will happen in the future. Professor du Sautoy examines how the flight of migrating birds obeys a simple and elegant code - a pattern of behavior as applicable to commuters passing through Grand Central Station as it is to serial killers planning their next attacks. While so much of life appears random, Du Sautoy shows how it is really governed by the code of chaos, in which small variations can cause vastly different outcomes, often referred to as the "butterfly effect."